(set-logic QF_SLIA)
(set-info :status sat)
(declare-fun v () String)
(declare-fun a () String)
(assert (not (str.in_re (str.++ v "z") (re.++ (str.to_re "b") (re.* (str.to_re (str.replace_all v v "")))))))
(assert (str.in_re (str.++ v "z" a) (re.++ (str.to_re "b") (re.* (str.to_re "z")))))
(check-sat)
